Recording apparatus

ABSTRACT

The recording medium is preferably a drafting film which has been printed with dark ink, and recording is accomplished in the preferred embodiment by selectively removing the ink using a fine stream of abrasive particles. These abrasive particles impinge on the recording medium to produce a record on the medium. The expended abrasive and ink residue is removed by a collection apparatus, including a vacuum manifold and a pressure manifold, which deposits the abrasive and residue in a collection chamber. A demand feed ink jet is selectively operated for erasing by redepositing ink in the desired pattern.

United States Patent Cotter Sept. 2, 1975 [54] RECORDING APPARATUS3,621,967 11/1971 Brown 197/18 3,683,212 8 1972 Z01 346 7 [76] Inventor:William L. Cotter, PO. Box 2045, 5 X

Salem, Mass. 01970 Primary Examiner-Joseph W. Hartary [22] Flled: 1973Attorney, Agent, or Firm-Wolf, Greenfield & Sacks [21] Appl. No.:403,824

Related U.S. Application Data [57] ABSTRACT [63] Continuation-impart ofSer. No. 395,822, Sept. 10, The recording medium is preferably adrafting m 1973 abandoned which has been printed with dark ink, andrecording is accomplished in the preferred embodiment by selec- [52]346/21 51/8 346/139 R tively removing the ink using a fine stream ofabrasive Clparti ese as e p c es on the re [58] Field of Search....l.{346/21,91 46,8l39 R, cording medium to produce a record on themedium 51/ 3] 17 B The expended abrasive and ink residue is removed by acollection apparatus, including a vacuum manifold [56] References cuedand a pressure manifold, which deposits the abrasive NI D STATES PATENTSand residue in a collection chamber. A demand feed 2,384,515 9/1945 Wise346/21 ink jet is selectively operated for erasing by redeposit-3,237,748 3/1966 Rifldn 197/181 ing ink in the desired pattern.3,309,712 3/1967 Cole 346/21 X 3,440,775 4/1969 Thomas 51/319 7 Claims,4 Drawing Figures l T T T T 1 ABRASIVE ABRASIVE FEED DISPENSER VAg/E 29g TO WRITE CONTROL u u l LOGIC 82 l FlLTER W I I VACUUM I PRESSURE PUMPPAIENIEII 2 I975 RECORDING MEDIUM SUBSTRATE OR HOLlgER RECORDER SIIEET 1[IF 2 RECORDING MEDIUM IO FIG. I

ABRASIVE FEED LINE 1 VACUUM LINE 1 PRESSURE LINE 1 I I I I I I I--ENcooER PULSES RECORD/ERASE HEAD FIG. 2

ABRASIVE DISPENSER TO WRITE CONTROL LOGIC VACUUM PRESSURE PUMP FIG 3PULS E GENERATOR INK SUPPLY 5 ERASE CONTROL ANOD 2e, ENCODER 0 Y ENCODERPULSES PULSES 29 N 94 X ENCODER PULSES PAIEI-IIEII SEP 2 975 NOZZLESHEET 2 BF 2 PRESSURIZED APBgSD|E /RE\ MIXIN CHAMBER 44 64 ABRASIVE FEEDVALVE MIXING SOLENOID 3/ VIBRATOR 6O AREA 56 TO CONTROL LOGIC RECORDINGAPPARATUS RELATED APPLICATION This is a continuation-in-part of mycopending application Ser. No. 395,822 filed Sept. 10, 1973.

FIELD OF THE INVENTION The present invention relates in general to arecording apparatus and associated method of recording data on an inkedfilm. This invention is also directed to a recording apparatus thatreadily performs both the re cording and erasing operations, and thatcan be used with a variety of different recording media such asphotographic film or glass.

BACKGROUND OF THE INVENTION There are many methods that presently existfor recording information on a recording medium. These methods andapparatus generally do not provide the ability of both recording anddeleting data from the same medium without the use ofa scheme such asmanual deletion. Many times the presence of an error is corrected byidentifying the error and then reproducing the entire record. This is,of course, time consuming and costly.

Accordingly, it is an object of the present invention to provide arecording apparatus and method of recording which is compatible withboth the addition and deletion of information from a recording medium.

Another object of the present invention is to provide an apparatus andmethod of recording data on a recording medium and which is of apermanent nature.

Still another object of the present invention is to provide a recordingapparatus which may be used with a larger variety of recording mediasuch as drafting film photographic film, glass, etc. Any of therecording methods presently used do not have this capability.

SUMMARY OF THE INVENTION To accomplish the foregoing and other objectsof this invention there is provided an apparatus for recording on amedium printed with an ink film. This apparatus generally comprises asupply of particles of an abrasive material, means coupled to the supplyfor expelling the particles from the supply under pressure, a nozzle,and means coupled intermediate the supply and nozzle for Selectivelydirecting the abrasive material in a confined stream against the medium.

In the disclosed embodiment the supply of particles comprises a vibratorand means for mixing a pressurized gas with the abrasive particles toexpel] the particles from the supply. The means for selectivelydirecting the abrasive material may be a solenoid that is both air andelectrically operated to either block or allow the passage of thecarrier gas and the abrasive material.

The dispensing nozzle is preferably surrounded by a vacuum manifold. Theabrasive particles which bounce off the recording surface, as well asthe removed ink particles, are collected by the vacuum manifold. Thisresidue is transported by the flow of air in the vacuum line to acollection chamber where the residue is deposited. In the disclosedembodiment the vacuum manifold is, in turn, surrounded by a pressuremanifold which dispenses a high velocity stream of air in the shape ofan annulus around the recording area. The pressure manifold establishesa pressure barrier to prevent the escape of abrasive material and aidsin directing or funneling the material to the vacuum manifold. When therecording medium is a film, or paper, the pressure manifold aids also inpreventing the vacuum from lifting the recording medium from itsmounting surface.

In the preferred embodiment of the invention recording is accomplishedby abraiding the ink film, and a demand feed ink jet is used to depositink over areas which were previously removed during the recordingprocess. However, in accordance with another aspect of the presentinvention the method of this invention can also be practiced, in oneembodiment, by using a film that has not been printed with ink. Withthis arrangement the recording is accomplished by the use of, forexample, a demand feed ink jet and erasing is accomplished by means ofthe abrasive nozzle discussed hercinabove.

BRIEF DESCRIPTION OF THE DRAWINGS Numerous other Objects, features andadvantages of the invention should now become apparent upon a reading ofthe following detailed description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a functional block diagram of the apparatus of the presentinvention;

FIG. 2 illustrates the writing head shown in FIG. I along with theabrasive feed valve and abrasive dispenser;

FIG. 3 shows the erase structure associated with the writing head ofFIG. 2; and

FIG. 4 shows in more detail the abrasive dispenser of FIG. 2.

DETAILED DESCRIPTION FIG. 1 shows a recording medium 10 supported by aholder 12. In the disclosed embodiment the recording medium ispreferably a drafting film that has been printed with a black ink.Writing is accomplished by se lectively removing the ink and erasing isaccomplished by reapplying the ink to previously recorded areas.

FIG. 1 also shows the writing head 14 and erase head 16 which isillustratively depicted as an inkjet l8 terminating in a dispensingnozzle 20.

The writing head and erase head are normally commonly mounted on amechanism which allows the heads to be moved over the surface of therecording medium. By controlling the motion of the head and the times atwhich these heads are operated, the recorder may be caused to drawlines, figures, or other graphic information. If data. once written, isto be deleted, an erase signal is coupled to the erase head causing theerase head to move into the relative position originally occupied by therecording device. An offset value may be introduced into the head-movingmechanism for controlling during the erase procedure. As depicted inFIG. 1, and discussed in more detail hereinafter the writing headcouples to a vacuum line, a pressure line, and a feed line. The erasehead is controlled from a pulse generator 24 whose output couples tocoil 19 of the inkjet 18. The ink jet 18 also couples to an ink supply28.

FIG. 2 shows in more detail the writing head 14. FIG. 2 also shows theabrasive feed valve 30 and abrasive dispenser 40. The abrasive dispenseris shown in more detail in FIG. 4. The dispenser 40 generally includes apressurized gas supply 42, a mixing chamber 44, and pressure regulator46 and 48. The mixing chamber 44 includes a top portion 50 forcontaining the abrasive powder 52.

A feed-tube 54 which is open at its ends couples to a relatively smallmixing compartment 56. A vibrator 60 is disposed at the bottom ofchamber 44 for vibrating the powder 52 and causing the abrasive powderto be fed down tube 54 to compartment 56. A pressurized gas from supply42 by way of regulator 46 is also coupled to compartment 56 for mixingwith the abrasive powder. The mixture is expelled by way of conduit 64when the abrasive feed-valve 30 is operated.

The abrasive feed-valve 30 is both electrically and gas operated and theregulator 48 which also coupled to valve 30 is for reducing the supplypressure to a value required by the valve 30. The valve 30 also includesa solenoid 31 which is electrically operated from control logic notshown in FIG. 4, and when the solenoid 31 is activated, the valve 30 isopened to permit the abrasive powder to be fed to nozzle 20.

The solenoid 31 shown in FIG. 4 may be controlled as disclosed by mycopending application for selectively writing by means of expelling thepressurized abrasive against the recording medium.

FIG. 2 shows the writing head 14 in more detail. In FIG. 2 the head 14includes the nozzle 20. This nozzle can be provided in different sizesdepending upon the thickness of the line that is to be drawn. Theabrasive nozzle is surrounded by a vacuum manifold 75 which collects theexpended abrasive material after impingement on the recording surface,as well as the ink particles removed from the surface. The expendedpowder is returned by means of a vacuum line 76 to a collector 80. Thevacuum line also continues through a filter 82 which prevents theabrasive material from entering the vacuum-pressure pump 86. Anothervacuum section 88 couples to the pressure manifold 90 which surroundsthe vacuum manifold 75. The nozzle 20 and manifolds 75 and 90 arepreferably concentrically arranged.

The pressure manifold 90 serves at least two purposes. One purpose is toestablish a pressure barrier which aids in funneling the expendedabrasive into the vacuum manifold. The other purpose is to prevent thevacuum manifold from causing the recording medium to lift off itsmounting surface because of the flow of air across the recordingsurface.

It is preferred that the powder be expended at a pressure ofapproximately 20-40 lbs. per square inch. The pressure used can bevaried to control the line density. In FIG. 4 the regulator 46 can beused for controlling the speed of cutting or abraiding of the recordingmedium. Also, different grades of abrasive powder can be applied to varythe density of the recorded data.

FIG. 3 shows a preferred embodiment of the ink dispensing or erasingmechanism in the form of a demand ink jet 18, ink supply 28, and controlmeans 29. The control means includes a pulse generator 24 which providesthe proper amplitude pulse and proper shaped pulse for driving the coil19 of the ink jet. The pulse generator is activated from gate 92 whichis an AND gate receiving an erase control signal on line 93 and anothersignal from OR gate 94. As long as the erase control signal is presenton line 93, and each time an encoder pulse appears then a pulse isgenerated from generator 24. In the embodiment disclosed in FIG. 3,which is similar to the drawing shown in my copending application both Xand Y pulses enable gate 94.

These pulses typically occur for every movement of 0.0025 inches ineither axis. As the deposited ink spe size may approximately be 0.010inches in diameter a line is then deposited on the recording medium asthe head moves.

In FIG. 3 the ink jet 18 may be a glass capillary tube which is drawn toa small orifice tip. The coil 19 may be in the form of a ferro electriccoating to which two leads are attached. A pulse or voltage appliedbetween the two leads causes a mechanical compression of the ferroelectric material and the glass capillary which forces a drop of inkfrom the capillary tip. This process is repeated at high speed to allowerasing of lines and characters as the jet is moved across the surfaceof the recording medium. The ink jet is driven by a pulse generator 24which shapes and amplifies the pulses to coil 19. In the disclosedembodiment drive pulses are derived from position encoders attached tothe mechanism which moves the heads over the surface of the recordingmedium. Other methods may also be used to dispense the ink such as arecording pen or an air brush.

In view of the obvious modifications that can be made in the embodimentsof the invention herein described and in view of the different forms ofthe invention it can take it is not intended to limit the invention tothe precise arrangements illustrated herein. Rather, it is intended thatthe scope of the invention be delimited by the appended claims and thatwithin that scope be included such structures as depart from theessential nature of the invention only by obvious changes or by thesubstitution of equivalence but do not alter the basic scheme of theinvention.

What is claimed is:

1. An apparatus for recording on a medium which has a removable filmdeposited thereon, said apparatus comprising; i

a supply of particles of an abrasive material, a nozzle, means coupledintermediate the supply and nozzle for selectively directing theabrasive material under pressure to the nozzle from where it is expelledin a confined stream against the medium,

means for collecting the expelled material including a collecting headdisposed about said nozzle,

said collecting head defining a pressure manifold and a vacuum manifold,

a collection chamber for the expelled particles,

a pump means,

and conduit means connecting in sequence the vacuum manifold, collectionchamber, pump means and pressure manifold, whereby the pump meanscreates a vacuum to draw expelled particles via the vacuum manifold tothe collection chamber.

2. An apparatus for dispensing a stream of abrasive particles to performwriting or erasing on a recording medium, said apparatus comprising;

a nozzle for directing the stream of abrasive particles,

an abrasive dispenser,

means coupled intermediate the nozzle and dispenser for selectivelyconveying the particles to the nozzle,

and means for collecting the expelled particles including,

a collection head enclosing the nozzle and defining a vacuum manifoldadjacent the nozzle and a pressure manifold adjacent the vacuum manifoldand remote from the nozzle relative to the vacuum manifold,

and means including a collection chamber and coupled to both the vacuummanifold and pressure manifold for drawing expelled particles throughthe vacuum manifold to the collection chamber.

3. The apparatus of claim 2 wherein said means for drawing expelledparticles includes a vacuum pressure pump and conduit meansinterconnecting in sequence the vacuum manifold, collection chamber,pump and pressure manifold for carrying said particles from the vacuummanifold to the collection chamber.

4. The apparatus of claim 2 wherein said pressure manifold is disposedabout said vacuum manifold so as to direct the expelled particles towardthe vacuum manifold.

5. The apparatus of claim 1 wherein said nozzle, vacuum manifold andpressure manifold are concentrically arranged.

6. The apparatus of claim 5 including a filter connected by sections ofthe conduit means between the collection chamber and the pump.

7. The apparatus of claim 2 wherein said abrasive dispenser includes asupply chamber, vibration means a source of pressurized gas, conduitmeans having a plurality of conduit sections, said vibration means forvi brating said supply chamber and a mixing chamber connected by aconduit section to the source and another conduit section to the meansfor selectively conveying and having means for receiving the vibratedparticles which are forced to the means for selectively conveying by thepressurized gas.

1. An apparatus for recording on a medium which has a removable filmdeposited thereon, said apparatus comprising; a supply of particles ofan abrasive material, a nozzle, means coupled intermediate the supplyand nozzle for selectively directing the abrasive material underpressure to the nozzle from where it is expelled in a confined streamagainst the medium, means for collecting the expelled material includinga collecting head disposed about said nozzle, said collecting headdefining a pressure manifold and a vacuum manifold, a collection chamberfor the expelled particles, a pump means, and conduit means connectingin sequence the vacuum manifold, collection chamber, pump means andpressure manifold, whereby the pump means creates a vacuum to drawexpelled particles via the vacuum manifold to the collection chamber. 2.An apparatus for dispensing a stream of abrasive particles to performwriting or erasing on a recording medium, said apparatus comprising; anozzle for directing the stream of abrasive particles, an abrasivedispenser, means coupled intermediate the nozzle and dispenser forselectively conveying the particles to the nozzle, and means forcollecting the expelled particles including, a collection head enclosingthe nozzle and defining a vacuum manifold adjacent the nozzle and apressure manifold adjacent the vacuum manifold and remote from thenozzle relative to the vacuum manifold, and means including a collectionchamber and coupled to both the vacuum manifold and pressure manifoldfor drawing expelled particles through the vacuum manifold to thecollection chamber.
 3. The apparatus of claim 2 wherein said means fordrawing expelled particles includes a vacuum pressure pump and conduitmeans interconnecting in sequence the vacuum manifold, collectionchamber, pump and pressure manifold for carrying said particles from thevacuum manifold to the collection chamber.
 4. The apparatus of claim 2wherein said pressure manifold is disposed about said vacuum manifold soas to direct the expelled particles toward the vacuum manifold.
 5. Theapparatus of claim 1 wherein said nozzle, vacuum manifold and pressuremanifold are concentrically arranged.
 6. The apparatus of claim 5including a filter connected by sections of the conduit means betweenthe collection chamber and the pump.
 7. The apparatus of claim 2 whereinsaid abrasive dispenser includes a supply chamber, vibration means asource of pressurized gas, conduit means having a plurality of conduitsections, said vibration means for vibrating said supply chamber and amixing chamber connected by a conduit section to the source and anotherconduit section to the means for selectively conveying and having meansfor receiving the vibrated particles which are forced to the means forselectively conveying by the pressurized gas.